Wilcoxia poselgeri is a unique succulent native to Texas and parts of Mexico, where it is abundant and widespread.
It thrives at low elevations up to 1150 meters above sea level.
In its native habitat, Wilcoxia poselgeri prefers woody vegetation to help support its thin stems. In addition, it also lives in the sandy soils of the desert-like brush.
The plant is unique with its shrubby yet erect shape. It rarely branches but sometimes sprawls as it matures.
The wilcoxia cactus is used in Mexico as a medicinal plant, treating broken bones in animals and offering anti-inflammatory properties.
Wilcoxia poselgeri is also known by the following scientific names:
- Echinocereus poselgeri Lem.
- Cereus poselgeri (Lem.) J.M.Coult.
- Echinocereus poselgeri Small
Ironically, the plant was named after an Assistant Surgeon in the military, not a botanist.
The plant was eponymously named in honor of Captain Timothy E. Wilcox (1840-1932), who was posted as Assistant Surgeon in Arizona and first identified the plant.
Some of the common names of Wilcoxia Poselgeri are:
- Pencil Cactus
- Lead Pencil Cactus
- Dahlia Cactus
- Dahlia Hedgehog Cactus
Quick Facts On Wilcoxia Poselgeri
- Family: Cactaceae
- Light: Full sun to light shade
- Temperature: 55° degrees Fahrenheit in winter
- Water: Little (drought tolerant)
- Fertilizer: Liquid fertilizer monthly during the growing season
- Propagation: Seeds or cuttings
- Common Problems: Scales, sunburn (brown spots)
Wilcoxia Poselgeri Care
What Does The Wilcoxia Poselgeri Look Like, And How Big It Grow?
Wilcoxia poselgeri is an epiphytic cactus that takes on a climbing or creeping habit.
While they grow erect when young, they often cling to bigger plants or trees as they mature.
Its slender stems give the plant its common name of Pencil Cactus, with a maximum diameter of ¾” of an inch. However, the pencil-thin stems can reach up to 5’ feet tall!
Like most cacti plants, each stem can be divided into ribs, usually 6 to 10 ribs per stem.
The plant’s areoles, tiny bumps that grow clusters of spines, are numerous, and each gives way to 10 to 15 short spines.
The areoles are also the cacti’s buds, from which the thorns form. Each areole produces one more prominent central spine, surrounded by 10 to 15 thorns.
In younger stems, the areoles also form a white tuft of fluffy hair.
The plant’s roots are pronounced tubers, roughly half an inch in diameter. Each plant has a maximum of 8 tubers.
These tubers are why this cactus plant is also called the Dahlia hedgehog cactus.
When Does Wilcoxia Poselgeri Flower? Are The Flowers Fragrant?
The Wilcoxia Poselgeri plant has beautiful flowers that are very showy. They bloom at the top of the plant’s thin stems and have pointed pink petals with a yellow center.
The flowers then form a unique fruit that is not quite an inch long and 6″ inches wide. This fruit is usually a green-brown color containing tiny black seeds.
Some gardeners say that the flowers have a mild fragrance, but it’s not a central feature of the plant.
What Are The Lighting Needs And Temperature Requirements?
Wilxocia poselgeri prefers full to partial sun and does better as an outside plant if you live in a warm climate.
If you live in a colder climate with dry winters, the plant is cold-hardy down to temperatures of 15° degrees Fahrenheit. However, it thrives in winter temperatures around 55° degrees Fahrenheit.
While it can withstand temperatures as low as 15° degrees Fahrenheit, you must live in a dry environment for it to survive the low temperatures.
This plant needs a cold and dry environment to rest during the winter. If your winters are wet, you will need to bring your plant indoors during the winter.
It’s important to note that this plant rests during the winter, so if you keep it indoors, do not place it in your warm living room between October and February.
Instead, it needs to be in a colder and arid environment where temperatures can be around 55° degrees Fahrenheit.
How And When To Water And Fertilize Wilcoxia Poselgeri?
Wilcoxia poselgeri needs watering, similar to other succulents. However, it’s a good idea to ensure that the plant never sits in excess water.
The soak and dry method is best to keep it evenly moist. First, soak the soil thoroughly, then let the soil dry out completely before watering again.
In addition, it’s essential that the plant is in a pot with adequate draining holes and you have well-draining soil.
Reduce the frequency of watering in the fall and stop watering in the winter. This plant is particularly susceptible to overwatering, especially in moist cold soil during winter.
Also, your plant will thrive best with monthly liquid fertilizer in the spring and summer.
What Is The Best Soil For Wilcoxia Cactus, And When Should You Transplant?
The Wilcoxia poselgeri plant thrives best in rich, well-draining soil.
In addition, many gardeners add a base layer of sand and a layer of pea gravel at the bottom of the pot to ensure drainage.
You can repot this plant every 2 to 3 years in the spring for new soil and nutrients, but it is not required annually.
Does Wilcoxia Cactus Need Special Grooming Or Maintenance?
The Wilcoxia poselgeri does not need any grooming or maintenance, which makes this plant a good choice for beginner gardeners.
How To Propagate Wilcoxia Plant?
When propagating your plant from cuttings, do the following:
- Carefully cut a leaf from the Pencil Cactus with a pair of clean shears.
- Before replanting, it’s a good idea to wait a few days to allow the cutting to be callous.
- Once the cutting is callous, place it in a pot with well-draining soil and water it once the soil is fully dry.
- In the spring and summer, ensure that it has access to sun and warmth to encourage growth.
This succulent is a slow grower, so even if its seeds can propagate, this method is not recommended.
However, if you want to try the seed method, plant them in a well-draining soil mixture with access to sun and warmth.
You can use this method outdoors if you live in a mild climate. Otherwise, indoor propagating is recommended.
Wilcoxia Poselgeri Pests And Diseases
Wilcoxia Poselgeri, also known as Dahlia Cactus, is generally resistant to pests and diseases, but you’ll want to watch out for scale bugs.
If you notice them on your Dahlia Cactus, you can remove them with Q-tips or a toothpick.
Also, while the plant loves the sun, direct afternoon sun can scorch the leaves. If this happens, you’ll notice that the stems turn brown in spots.
Thankfully, you can adjust the lighting, either by moving the plant to another location or providing temporary shade for the plant.
Suggested Lead Pencil Cactus Uses
The Lead Pencil cactus plant is an excellent choice for drought-tolerant, succulent gardens where temperatures are mild year-round.
The plant also pairs well with aloes and agaves.